He's a fellow without time (5)
I believe the answer is:
peter
'he's' is the definition.
(I've seen this before)
'a fellow without time' is the wordplay.
'a fellow' becomes 'peer' (both can mean an equal).
'without' is an insertion indicator ('without' can be similar in meaning to 'outside').
'time' becomes 't' (abbreviation).
'peer' enclosing 't' is 'PETER'.
(Other definitions for peter that I've seen before include "Man's name" , "Play high card before low" , "Rock-like apostle" , "In whist, play" , "One of the Apostles" .)